PARIS — A European investigator said Tuesday he has found mounting indications the United States illegally held detainees in Europe but then hurriedly shipped out the last ones to North Africa a month ago when word leaked out.

Both countries have denied any involvement and Marty said he believes no prisoners are now being held by the U.S. in Europe. The CIA declined to comment.

“To my knowledge, those detainees were moved about a month ago, maybe a little more,” he told reporters after briefing the legal committee of the Council of Europe, a human rights watchdog, on his findings. “They were moved to North Africa.”

Asked by The Associated Press on the sidelines of the meeting to which North African country detainees might have been moved, he said: “I would imagine that it would be Morocco — up to you to confirm it.”

Moroccan government spokesman Nabil Benabdellah denied any connection to such prisons when reports of the transfers surfaced last week. “We have nothing to do with and we have no knowledge about this subject,” he told the AP.

The Washington Post first reported the alleged existence of secret prisons in eastern Europe and other countries on Nov. 2.

The newspaper did not name the countries, but the New York-based Human Rights Watch said it had evidence indicating the CIA transported suspected terrorists captured in Afghanistan to Poland and Romania. The conclusion was based on an analysis of flight logs of CIA aircraft from 2001 to 2004 obtained by the group.

European officials say such prisons would violate the continent’s human rights principles.

Marty told the council’s legal committee information gathered so far “reinforced the credibility of the allegations concerning the transfer and temporary detention of individuals, without any judicial involvement, in European countries.”

“Legal proceedings in progress in certain countries seemed to indicate that individuals had been abducted and transferred to other countries without respect for any legal standards,” he said. Marty was expected to present a full report to the council’s parliamentary assembly in late January.

The investigator told reporters he could not offer proof that secret detention centers existed. But he cited two suspected cases of detainees held by U.S. authorities in Europe as signs that suspects were held at least temporarily in Europe.

The cases cited were the alleged February 2003 kidnapping of Egyptian cleric Osama Moustafa Hassan Nasr by the CIA in Milan, Italy; and claims by Khaled al-Masri, a Lebanese-born German, that the agency took him to Afghanistan and tortured him after mistakenly identifying him as being linked to al-Qaida. Al-Masri said he was released in Albania in May 2004.

Marty told reporters that his aim was not to expose any U.S. wrongdoing but to ensure that the Council of Europe’s 46 member states did not violate its rules.

He said he had asked the council’s members for better cooperation in the investigation, expressing concern that some may not want to ruffle feathers in Washington for political or economic reasons. Marty singled out Switzerland as a country that did not seem “very motivated to shine all the light” on the issue of alleged CIA overflights and landings in Geneva.

Marty has asked for air traffic logs from European countries as he seeks to trace flight patterns for several dozen suspected CIA airplanes. He also has asked for satellite images of the Sczytno-Szymany airport in northeastern Poland and the Mihail Kogalniceanu Air Base in Romania.

“We have clues that show that (Poland and Romania) — and perhaps others — were implicated, insofar as people were temporarily held there. Not in camps or classic prisons, but temporary stays,” Marty said.

After hearing Marty’s presentation, legal committee member Tony Lloyd said: “The really difficult thing is the idea that there is a kind of legal black hole in the middle of Europe.”

Marty said some governments may not have known of detention centers on their own soil and it was “still too early to assert that there had been any involvement or complicity of member states in illegal actions.”

The senator also was critical of the United States, saying he “deplores the fact that no information or explanations” were provided by Secretary of State Condoleezza Rice, who faced repeated questions about the CIA prison allegations on her recent visit to Europe.

Rice has said the United States acts within the law and argued that Europeans are safer because of tough U.S. tactics, but she refused to discuss intelligence operations or address questions about clandestine CIA detention centers.